Conventional Conditions Research Articles

The Green Cooling Factor: Eco-Innovative Heating, Ventilation, and Air Conditioning Solutions in Building Design

This research investigates the compatibility of conventional air conditioning with the principles of green building, highlighting the need for systems that enhance indoor comfort while aligning with environmental sustainability. Though proficient in regulating indoor temperatures, conventional cooling systems encounter several issues when incorporated into green buildings. These include energy waste, high running costs, and misalignment with eco-friendly practices, which may also lead to detrimental environmental effects and potentially reduce occupant comfort, particularly in retrofit situations. Given the emphasis on sustainability and energy conservation in green buildings, there is a pressing demand for heating, ventilation, and air conditioning (HVAC) solutions that support these goals. This study emphasises the critical need to reconsider traditional HVAC strategies in the face of green building advances. It advocates for the adoption of innovative HVAC technologies designed for eco-efficiency and enhanced comfort. These technologies should integrate seamlessly with sustainable construction, use greener refrigerants, and uphold environmental integrity, driving progress towards a sustainable and occupant-friendly built environment.

Treatment of intrauterine adhesions in rats with hypoxia-cultured BMSC-derived exosomes

Objective: To perform intrauterine adhesion modeling, and to investigate the repair effect of hypoxic treated bone marrow mesenchymal stem cells (BMSC) and their derived exosomes (BMSC-exo) on endometrial injury. Methods: BMSC and their exosomes BMSC-exo extracted from rats' femur were cultured under conventional oxygen condition (21%O2) or hypoxia condition (1%O2). Intrauterine adhesion modeling was performed on 40 healthy female SD rats by intrauterine injection of bacterial lipopolysaccharide after curettage. On the 28th day of modeling, 40 rat models were randomly divided into five groups, and interventions were performed: (1) NC group: 0.2 ml phosphate buffered solution was injected into each uterine cavity; (2) BMSC group: 0.2 ml BMSC (1×106/ml) with conventional oxygen culture was injected intrauterine; (3) L-BMSC group: 0.2 ml of hypoxic cultured BMSC (1×106/ml) was injected intrauterine; (4) BMSC-exo group: 0.2 ml of BMSC-exo cultured with conventional oxygen at a concentration of 500 μg/ml was injected into the uterine cavity; (5) L-BMSC-exo group: 0.2 ml hypoxic cultured BMSC-exo (500 μg/ml) was injected intrauterine. On the 14th and 28th day of treatment, four rats in each group were sacrificed by cervical dislocation after anesthesia, and endometrial tissues were collected. Then HE and Masson staining were used to observe and calculate the number of glands and fibrosis area in the endometrium. The expressions of angiogenesis related cytokines [vascular endothelial growth factor A (VEGFA) and CD31], and fibrosis-related proteins [collagen-Ⅰ, collagen-Ⅲ, smooth muscle actin α (α-SMA), and transforming growth factor β1 (TGF-β1)] in endometrial tissues were detected by western blot. Results: (1) HE and Masson staining showed that the number of endometrial glands in L-BMSC group, BMSC-exo group and L-BMSC-exo group increased and the fibrosis area decreased compared with NC group on the 14th and 28th day of treatment (all P<0.05). Noteworthily, the changes of L-BMSC-exo group were more significant than those of BMSC-exo group (all P<0.05), and the changes of BMSC-exo group were greater than those of BMSC group (all P<0.05). (2) Western blot analysis showed that, compared with NC group, the expressions of collagen-Ⅲ and TGF-β1 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group decreased on the 14th and 28th day of treatment (all P<0.05). As the treatment time went on, the expressions of fibrosis-related proteins were different. Compared with BMSC group, the expressions of collagen-Ⅲ, α-SMA and TGF-β1 in the BMSC-exo group and L-BMSC group decreased on the 28th day (all P<0.05). Moreover, the expressions of collagen-Ⅲ and TGF-β1 in L-BMSC-exo group were lower than those in BMSC-exo group on the 28th day (all P<0.05). And the expressions of collagen-Ⅰ, α-SMA and TGF-β1 in L-BMSC-exo group were lower than those in L-BMSC group on the 28th day (all P<0.05). (3) The results of western blot analysis of VEGFA and CD31 showed that, the expressions of VEGFA and CD31 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group increased on the 14th and 28th day of treatment compared with NC group (all P<0.05). Treatment for 28 days, the expressions of VEGFA and CD31 in BMSC-exo group and CD31 in L-BMSC group were higher than those in BMSC group (all P<0.05). Moreover, the expressions of VEGFA and CD31 in L-BMSC-exo group were higher than those in BMSC-exo group and L-BMSC group on the 28th day (all P<0.05). Conclusions: Treatment of BMSC and their exosomes BMSC-exo with hypoxia could promote endometrial gland hyperplasia, inhibit tissue fibrosis, and further repair the damaged endometrium in rats with intrauterine adhesion. Importantly, hypoxic treatment of BMSC-exo is the most effective in intrauterine adhesion rats.

Exploring global accessibility of deep ocean water for sea water air conditioning (SWAC) process: Identifying feasibility areas depending on temperature source

Sea Water Air Conditioning (SWAC) technology is a highly efficient alternative to conventional air conditioning system using renewable marine energy to provide cooling to buildings. However, its implementation requires access to Deep Ocean Water (DOW) at 4–5 °C, thus SWAC is only viable in coastal regions. Furthermore, one of the major obstacles to its global development is the investment cost that remains high. This cost is strongly linked to the bathymetry of the installation location as it determines the length of the drawing pipeline, which accounts for the largest share of the investment cost. Knowing the temperature and bathymetry profiles will enable the establishment of the financial viability of SWAC technology in a specific location. This paper presents an analysis identifying areas of feasibility on a worldwide scale for standard SWAC implementation first. Then, it explores an alternative design with a higher drawing point for seawater at 12 °C (coupled with a High Temperature District Cooling), which reduces the cost by shortening the drawing pipeline and allows for more locations to be suitable for this technology. Additionally, the impact of the El Niño/Southern Oscillation (ENSO) is also considered since a shallower drawing point makes it more sensitive to temperature variations.

Adenine methylation is very scarce in the Drosophila genome and not erased by the ten-eleven translocation dioxygenase.

N6-methyladenine (6mA) DNA modification has recently been described in metazoans, including in Drosophila, for which the erasure of this epigenetic mark has been ascribed to the ten-eleven translocation (TET) enzyme. Here, we re-evaluated 6mA presence and TET impact on the Drosophila genome. Using axenic or conventional breeding conditions, we found traces of 6mA by LC-MS/MS and no significant increase in 6mA levels in the absence of TET, suggesting that this modification is present at very low levels in the Drosophila genome but not regulated by TET. Consistent with this latter hypothesis, further molecular and genetic analyses showed that TET does not demethylate 6mA but acts essentially in an enzymatic-independent manner. Our results call for further caution concerning the role and regulation of 6mA DNA modification in metazoans and underline the importance of TET non-enzymatic activity for fly development.

Plane wave reflection in micro-structural piezomagnetic-flexomagnetic solid with impedance boundary conditions

The second-order gradient theory is reliable to predict the behavior of mechanical phenomena such as wave scattering, vibration, and buckling in nano/micro-structures. This theory incorporates size-dependent effects including strain-gradient elasticity and micro-inertia, crucial for constitutive modeling of piezomagnetic-flexomagnetic crystals. These small-scale size effects can have significant impact on the sensing mechanism of nanoscale transducers used in structural health monitoring (SHM) and nondestructive testing (NDT). In this article, we address the scattering of a plane wave (P-type longitudinal wave) in a piezomagnetic-flexomagnetic solid halfspace after it reflects from an open surface. The secular equation of quasi plane ( qP ) wave and multiple wave modes generated after reflection have been obtained analytically using non-classical governing equations. Impedance boundary conditions have been considered and conventional stress-free boundary conditions have been obtained as its case. Unlike a conventional piezomagnetic medium, five different wave modes have been traced after reflection (two different surface wave modes are present due to the gradient elasticity and micro-inertia effect). Closed expressions of amplitude ratios and energy flux ratios of reflected waves have been formulated from the system of linear equations. By taking a suitable numerical example, amplitude ratios and energy flux ratios for reflected waves have been plotted with respect to incidence angle. Detailed discussions have been made to understand the influence of impedance boundary and flexomagnetic effect on those ratios. The numerical results have been validated by energy conservation law. This investigation may provide necessary guidelines to understand the plane wave characteristics in micro-structural smart solid structures.

Adenine methylation is very scarce in the Drosophila genome and not erased by the ten-eleven translocation dioxygenase

N6-methyladenine (6mA) DNA modification has recently been described in metazoans, including in Drosophila, for which the erasure of this epigenetic mark has been ascribed to the ten-eleven translocation (TET) enzyme. Here, we re-evaluated 6mA presence and TET impact on the Drosophila genome. Using axenic or conventional breeding conditions, we found traces of 6mA by LC-MS/MS and no significant increase in 6mA levels in the absence of TET, suggesting that this modification is present at very low levels in the Drosophila genome but not regulated by TET. Consistent with this latter hypothesis, further molecular and genetic analyses showed that TET does not demethylate 6mA but acts essentially in an enzymatic-independent manner. Our results call for further caution concerning the role and regulation of 6mA DNA modification in metazoans and underline the importance of TET non-enzymatic activity for fly development.

The Mining Industry's Role in Enhanced Weathering and Mineralization for CO2 Removal.

Enhanced weathering and mineralization (EWM) aim to remove carbon dioxide (CO2) from the atmosphere by accelerating the reaction of this greenhouse gas with alkaline minerals. This suite of geochemical negative emissions technologies has the potential to achieve CO2 removal rates of >1 gigatonne per year, yet will require gigatonnes of suitable rock. As a supplier of rock powder, the mining industry will be at the epicenter of the global implementation of EWM. Certain alkaline mine wastes sequester CO2 under conventional mining conditions, which should be quantified across the industry. Furthermore, mines are ideal locations for testing acceleration strategies since tailings impoundments are contained and highly monitored. While some environmentally benign mine wastes may be repurposed for off-site use─reducing costs and risks associated with their storage─numerous new mines will be needed to supply rock powders to reach the gigatonne scale. Large-scale EWM pilots with mining companies are required to progress technology readiness, including carbon verification approaches. With its knowledge of geological formations and ore processing, the mining industry can play an essential role in extracting the most reactive rocks with the greatest CO2 removal capacities, creating supply chains, and participating in life-cycle assessments. The motivations for mining companies to develop EWM include reputational benefits and carbon offsets needed to achieve carbon neutrality.

Enantioselective Catalytic Aldol Reactions in the Presence of Knoevenagel Nucleophiles: A Chemoselective Switch Optimized in Deep Eutectic Solvents Using Mechanochemistry.

In the presence of different nucleophilic Knoevenagel competitors, cyclic and acyclic ketones have been shown to undergo highly chemoselective aldol reactions with aldehydes. In doing so, the substrate breadth for this emerging methodology has been significantly broadened. The method is also no longer beholden to proline-based catalyst templates, e.g., commercially available O-t-Bu-L-threonine is advantageous for acyclic ketones. The key insight was to exploit water-based mediums under conventional (in-water) and non-conventional (deep eutectic solvents) conditions. With few exceptions, high aldol-to-Knoevenagel chemoselectivity (>10:1) and good product profiles (yield, dr, and ee) were observed, but only in DESs (deep eutectic solvents) in conjunction with ball milling did short reaction times occur.

BF3@K10: An Efficient Heterogeneous Montmorillonite Catalyst for the Halogenation of N-Heterocycles

AbstractHalogenated N-heterocycles are an essential structural building block in medicinal chemistry. Herein, we describe an economical and efficient protocol for the regioselective halogenation of several N-heterocycles (pyrimidines, a pyrazole, 2-aminopyridine, theophylline, and an imidazo[1,2-a]pyridine) with BF3-doped montmorillonite (BF3@K10). The new catalyst was characterized by FTIR and 11B NMR spectroscopy, XRD, SEM, and EDS. The developed strategy provides easy and fast access to iodo-, bromo-, and chloro-N-heterocycles under mild conditions. This method was used to synthesize nine new halogenated pyrimidine derivatives. The reaction is simple and general, affording good to excellent yields of products under conventional heating or microwave conditions in the presence of BF3@K10 as an ecofriendly, inexpensive, and efficient catalyst. This protocol is clearly superior to the conventional route because it offers short reaction times, high yields, and easy workup.

Performance of Heat Pipe with Different Working Fluid on Harvesting Wasted Heat Energy at Air Cooled Split Unit

These days, life would not be comfortable without air conditioning which leads to high power consumption due to air conditioning and subsequently increases the carbon footprint. In this research, verification was done on the capability of increasing superheat to improve the performance of the air-cooled split unit and the effect of power consumed by the air conditioning system. The superheat was increased by the heat harvested from the condensing unit of the air-cooled split unit by using a heat pipe. The heat pipe was charged with water, R134a, and R600a with a 100% filling ratio and 90 and 70 inclination angles. K-Type thermocouples, pressure gauges, and power meter were used in data collection. According to data analysis, water with a 90 inclination angle of heat pipe showed the best performance compared to other fluids because of its ability to increase superheat by approximately 32% compared to R600a which increased only approximately 6.5% compared to normal conventional air conditioning. However, it demonstrated that a rise in the superheat at the suction line and a rise in the Coefficient of Performance cannot guarantee a fall in energy usage. This was due to an increase of superheat by the water heat pipe at 90 angle inclination indicating approximately a 28.8% increase in power consumption.

Shear behaviour of loess under varied drainage conditions subjected to monotonic and cyclic loads

The role of drainage conditions in altering the shear behaviour of loess is a fundamental concern, yet remaining unclear in the current literature. This paper presents an experimental investigation into the problem on saturated intact loess through static and cyclic triaxial tests. Four types of drainage conditions were controlled during shearing, including drained, undrained, water-absorbing and partially drained conditions. Results from the static triaxial test revealed that the loess exhibited a strain-hardening behaviour in the drained condition. When the drainage of the loess sample was gradually restricted, it showed strain-softening behaviour, and the lowest shear strength occurred in the sample under the water-absorbing condition. A fairly good correlation has been established between the strain increment ratio and the stress ratio at the asymptotic state. When subjected to the cyclic loads, the loess sample demonstrated the cyclic mobility type of failure mode. A smaller number of cycles were found at failure for the loess samples under the water-absorbing condition than that under the conventional undrained condition. Of a particular interest was the partially drained condition. The mean effective stress of the loess sample firstly reduced, and it then regained as the cyclic load gradually proceeded. At the meanwhile, the excess pore water pressure of the sample reduced after reaching a peak value. In this study, the dynamic elastic modulus and the damping ratio of the loess samples were also examined. Compared with the undrained case, the dynamic elastic modulus is greater under the partially drained condition, and it is lower under the water-absorbing condition. Accordingly, an opposite trend was found for the damping ratio. The above experimental results provide evidences on how the drainage conditions expedite or retard the occurrence of shear failure in loess, confirming the significant impact of the drainage conditions on the shear behaviour of loess.

Assessment of methane production, disintegration, and biodegradation potential of bioplastic waste in anaerobic digestion systems

The suitability of bioplastics for treatment in anaerobic digestion and composting plants is not always clear despite their increasing popularity as an alternative to oil-based polymers. This study aims to estimate the anaerobic degradation of various combinations of bioplastics (cellulose acetate, polylactic acid (PLA) and polybutylene succinate (PBS)), filler (organic – gelatine – and inorganic) and plasticizer (triacetin) combinations, under conventional industrial digestion conditions. The investigation encompasses the evaluation of both physical (disintegration) and biological degradation processes, along with the modelling of their methane production utilizing various iterations of the Gompertz-type model. Results indicate that, during typical industrial residence time, cellulose-based bioplastics exhibit high methane yield (approximately 500 NmlCH4/gVS) and near-complete degradation (both physical and biological), while PLA has minimal biodegradation (11%) and low methane yield (59 NmlCH4/gVS). PBS-gelatine blends generate a significant amount of methane early in the digestion process (174 and 116 NmlCH4/gVS for flakes and pieces, respectively) but do not achieve full degradation. These findings suggest that the effectiveness of bioplastics degradation varies based on their composition, and further research is needed to optimize their treatment in common industrial facilities.

Training on Preparing Physical Condition Test Instruments for Pb Badminton Athletes. Brilliant

The expected goal is to create trainers who have knowledge about training in preparing physical condition test instruments for PB badminton athletes. Gemilang understands the importance of the physical condition components of badminton in Mataram. improve the performance of all Mataram City athletes effectively, efficiently and modernly. Mitra's problem is that the trainers lack knowledge regarding training in preparing physical condition test instruments for PB badminton athletes. Glorious, and many trainers still carry out conventional physical conditions without using sports science technology that is developing in the field of sports. The urgency of the problem is that there are no guidelines for the physical condition test instruments used by PB. The Glorious City of Mataram, is only conventional, not programmed to be varied, effective, the coach's experience of being an athlete is not the solution that is obtained. The solution method is by holding socialization, training, mentoring and evaluation analysis. Training on preparing physical condition test instruments for PB badminton athletes. A good performance according to this branch of sport. So that the training guidelines for preparing test instruments can be used as a basis for coaches to determine the physical condition of Badminton athletes. It is hoped that the results of the training service research will allow coaches to develop test instruments and measure physical conditions as reference material in formulating training programs so that they can improve the performance of badminton athletes. The conclusion is that there is knowledge about training in preparing physical condition test instruments for PB badminton athletes. Brilliant. provide a significant impact on systematic physical condition tests, effectively and efficiently to improve the performance of Mataram badminton athletes.

A Powerful Prediction Framework of Fracture Parameters for Hydraulic Fracturing Incorporating eXtreme Gradient Boosting and Bayesian Optimization

In the last decade, low-quality unconventional oil and gas resources have become the primary source for domestic oil and gas storage and production, and hydraulic fracturing has become a crucial method for modifying unconventional reservoirs. This paper puts forward a framework for predicting hydraulic fracture parameters. It combines eXtreme Gradient Boosting and Bayesian optimization to explore data-driven machine learning techniques in fracture simulation models. Analyzing fracture propagation through mathematical models can be both time-consuming and costly under conventional conditions. In this study, we predicted the physical parameters and three-dimensional morphology of fractures across multiple time series. The physical parameters encompass fracture width, pressure, proppant concentration, and inflow capacity. Our results demonstrate that the fusion model applied can significantly improve fracture morphology prediction accuracy, exceeding 0.95, while simultaneously reducing computation time. This method enhances standard numerical calculation techniques used for predicting hydraulic fracturing while encouraging research on the extraction of unconventional oil and gas resources.

High-intensity green light potentially activates the actinorhodin biosynthetic pathway in Streptomyces coelicolor A3(2).

The development of practices that enhance the potential of actinomycetes as major antibiotic producers is a challenge in discovering new secondary metabolites. Light, an essential external stimulus for most microorganisms, could be exploited to manipulate their physiological processes. However, the effects of monochromatic green light on the production of secondary metabolites in actinomycetes have not yet been reported. In this paper, we report a novel and simple method that uses high-intensity monochromatic green light to potentially induce the production of cryptic secondary metabolites in the model actinomycete Streptomyces coelicolor A3(2). Using actinorhodin (ACT), a blue-pigmented antibiotic, and undecylprodigiosin (RED), a red-pigmented antibiotic, as indicators, we found that irradiation with high-intensity monochromatic green light-emitting diodes promoted sporulation, significantly decreased RED production, and increased ACT production. Semi-quantitative reverse transcription-polymerase chain reaction and western blot analyses revealed, for the first time, that stimulation with green light accelerated the expression of ActII-ORF4, a pathway-specific regulator of ACT biosynthesis in S. coelicolor A3(2). This approach of stimulating secondary metabolite biosynthesis pathways in actinomycetes by irradiation with high-intensity monochromatic green light is expected to facilitate the discovery of cryptic antibiotics that are not typically produced under conventional dark culture conditions. However, the effective intensity and duration of irradiation with green light that are required to activate these metabolite pathways may vary markedly among actinomycetes.

Cooling Potential Evaluation of a Ground Heat Exchanger in a Tropical Climate: A Case Study of an Office Building

The main implications of the hot-humid climate characteristics stipulate the need for cooling indoor environments. Ground thermal characteristics can be exploited in the search for sustainable ways to cool the indoor environment. Thus, this work aims to assess the cooling potential of the ground thermal characteristics through a vertical ground heat exchanger (VGHE) in a tropical climate such as Panama City via dynamic simulation. This potential is evaluated in a two-stories office building complying with Panama’s building regulation requirements, where a VGHE system is designed to cover the cooling needs. Since underground temperature data are unavailable, parametric and sensitivity analyses are carried out. For sizing the VGHE, a vertical ground system is chosen since this allows a better configuration in the installation for a building with large cooling demands and eliminates the need for large amounts of land. A difference of 33.52% (4481.4 kWh) in the electricity consumption for cooling was obtained compared to a conventional air conditioning system, which translates into a 770.80$ saving (0.172$/kWh). These results confirm that the system studied for air conditioning is feasible since it could provide positive results in thermal comfort and energy savings for the user.

Experimental and Hybrid Numerical Analytical Approach of an Earth-to-Air Heat Exchanger

Abstract The primary goal of this paper is to assess the thermal behaviour of Earth-to-Air Heat Exchanger (EAHE) under continuous operation mode during the cooling period in warm climatic conditions. An experimental setup was conducted in Biskra University (Algeria) to test the ability to use EAHE as an alternative solution to conventional air conditioning systems. Besides, a transient numerical approach for the flowing air within the EAHE was developed using energy balance equations, discretised by the implicit finite differences method and solved by Thomas method. Furthermore, the transient temperature profile of the soil around the EAHE was investigated in order to determine the adiabatic radius of the soil as a function of the duration of operation. In this context, a transient semi-analytical model was integrated to the air model to estimate the transient EAHE’s performance deterioration. This deterioration is produced by the thermal saturation of the soil, which is influenced by the heat released from the air inside the pipe. Results showed that continuous operation for a duration of four days has minimal impact on the outlet air temperatures due to the implementation of night purging. Furthermore, the design and thermal efficiency of the EAHE are impacted by factors such as higher air velocity and reduced soil thermal conductivity.

Application of human platelet lysate in chondrocyte expansion promotes chondrogenic phenotype and slows senescence progression via BMP–TAK1–p38 pathway

Osteoarthritis (OA) is one of the most common musculoskeletal degenerative. OA treatments are aiming to slow down disease progression; however, lack of cartilage regeneration efficacy. Autologous chondrocyte implantation (ACI) is a promising cartilage-regeneration strategy that uses human articular chondrocytes (HACs) as cellular materials. However, the unreadiness of HACs from prolonged expansion, cellular senescence, and chondrogenic dedifferentiation occurred during conventional expansion, thus, minimizing the clinical efficacy of ACI. We aimed to examine the effects of a human platelet lysate (HPL) as an alternative human-derived HAC medium supplement to overcome the limitations of conventional expansion, and to explain the mechanism underlying the effects of HPL. During passages 2–4 (P2-P4), HPL significantly increased HAC proliferation capacities and upregulated chondrogenic markers. Simultaneously, HPL significantly reduced HAC senescence compared with conventional condition. HACs treated with LDN193189 exhibited a reduction in proliferation capacity and chondrogenic marker expression, whereas the HAC senescence increased slightly. These findings indicated involvement of BMP-2 signaling transduction in the growth-assistive, anti-senescent, and chondrogenic-inductive properties of HPL, which demonstrated its beneficial effects for application as HAC medium supplement to overcome current expansion limitations. Finally, our findings support the roles of platelets in platelet-rich plasma as a promising treatment for patients with OA.

MICROTENSILE BOND STRENGTH OF UNIVERSAL ADHESIVE TO DENTIN AFTER ER: YAG LASER PRETREATMENT WITH DIFFERENT CONDITIONING MODES - AN IN VITRO STUDY

Adhesion to dentin remains challenging due to its complex nature that prevents complete infiltration of hydrophobic monomer to hydrophilic dentinal substrate. Recently, Er:YAG laser has been used in dentin pretreatment to enhance the bond strength. A deficient hybrid layer is formed following laser etching as it causes thermal damage and collagen denaturation of dentinal substrate. As the results are controversial, attempts are made to modify laser etching technique with respect to energy density, pulse duration and water spray. Thus, the present study aimed to evaluate the influence of Er:YAG laser conditioning of dentin by activation of Chlorhexidine collagen stabilising agent on the bond strength. Samples included 60 freshly extracted premolar which were divided into three groups (n=20) based on the protocol of dentin pretreatment done: Group 1 (Control) - Phosphoric acid etching followed by universal adhesive; Group 2 (Experimental) - Conventional Er:YAG laser dentioning; Group3 (Experimental) - Er:YAG laser dentin conditioning with coronal reservoir of 0.12% Chlorhexidine. Occlusal class 1 cavity was prepared on the samples followed by which dentin conditioning protocol was carried out for the respective groups. Universal adhesive was applied followed by Composite resin restoration. 1000 cycles of Thermocycling was done and the samples were sectioned to obtain microsections. Microtensile bond strength values were obtained by subjecting the specimens to Universal testing machine.Highest microtensile bond strength value was obtained for group 1 followed by group 3 with least value obtained for Group2 with statistically significant values between the groups. (p&lt;0.0001). Within the limitations of the present invitro study, it can be concluded that preetching with phosphoric acid increases the bond strength of universal adhesive to dentin. Laser conditioning of dentin through activation of chlorhexidine provided better bond strength value of universal adhesive when compared to conventional laser dentin conditioning.

A novel iodo bridged 1D CuI coordination polymer containing N,N-bidentate Schiff base ligand: Synthesis, structure, theoretical studies, electrochemical properties, and catalytic activity in the synthesis of tetrahydropyrimidines

In this study, a new 1D polymeric Cu(I) complex [Cu(L2Cl)I]n, where L = N,N′-bis(2-chlorobenzylidene)ethane-1,2-diamine, was synthesized and characterized using different analytical approaches, comprising 1H NMR, FT-IR, and CHN analysis. The geometrical features of the complex were determined through the single crystal X-ray diffraction (SC-XRD) method, which revealed that the copper atom is coordinated to the N atoms of the Schiff base. The bond angles surrounding Cu(I) ion indicated a somewhat distorted trigonal planar geometry of the complex. Hirshfeld surface analysis (HSA) was used to investigate the non-covalent intermolecular interactions, while theoretical studies were conducted utilizing DFT with B3P86/Def2-TZVP level of theory. The consistency between theoretical findings and experimental bond lengths of the [Cu(L2Cl)I]n confirmed the reliability of the theoretical conclusions. To better understand the intermolecular charge transfer features of the [Cu(L2Cl)I]n, the natural bond orbital as well as Atoms in Molecules analyses were also performed. The electrochemical behavior of the Cu(I) complex was explored at 25 °C using cyclic voltammetry in a pH 7.0 buffered solution. It is established that the quasi-reversible mechanism is consistent with the Cu(II)/Cu(I) redox system. Additionally, the catalytic action of this complex as a new catalyst was evaluated in the synthesis of derivatives of tetrahydropyrimidine by reacting 1,3-propylenediamine with various aryl nitriles under conventional thermal conditions.